The Plugged-In Continental Shelf |
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Part 2: Remote sensors beneath the sea are the cutting edge of marine geology
While there's certainly lots of science to be done in the deep ocean, the seas near the continents have plenty of challenges too. And today's nearshore observatories, installed permanently on the bottom, are making as many breakthroughs as the sexy deep platforms. In fact, one program of this type may make as big a spash as the Apollo space program.
LEO-15, the Long-Term Environmental Observatory at 15 meters depth off the coast of New Jersey, may be the oldest seafloor data station still in business. It consists of two "nodes," 5 and 7 kilometers offshore, each of which monitors conditions around the clock. The data is served onto the Web, and the instruments are controlled from shore through the power/data cable.
LEO-15 is not in a quiet abyss suitable for seismic deep-Earth studies; rather, it lies amid sediments scoured by tidal currents and storm surges from the Atlantic Ocean. But currents and surges are important data for understanding the behavior of the oceans, and they have very practical value for seagoing people of all kinds. For instance, upwellings of deep water can affect the local fishing business; waves can be monitored safely even during hurricanes; consequences of offshore dumping can be modeled and mitigated.
HUGO, the Hawaii Underwater Geo-Observatory, is an ambitious project that in 1997 installed an instrumented titanium platform on the summit of the submerged active volcano Loihi, south of Hawaii island. The power and data cable runs 47 kilometers from Honuapo Bay out to the platform, located in 1200 meters of water. Unfortunately, the power failed after six months of operation, but the HUGO scientists haven't given up. The HUGO Web site is still there too, with sound files of the volcano's activity and some whale songs recorded by the hydrophone.
Loihi is the newest volcano in the Hawaiian chain, and studying it gives us insight into the early stages of the older islands in the chain. It's also the leading edge of the Hawaii hotspot track. Loihi is a useful place to put a seismometer for helping to pinpoint earthquakes throughout the Big Island. And finally, the volcano could be a threat to the lands nearby, so having sensors in place could warn us of dangerous activity.
The technology of these cable-powered observatories is progressing slower than you'd think. The sea is very hard on equipment, for one thing, and for another, funding for this kind of research can be as fickle as the sea winds. Temporary deployments and experiments continue in various places, but the long-term data series that are the lifeblood of natural science are far from secure.
NEPTUNE Program image
The key to success may be to engage the public. That's how the Apollo program brought Americans to the Moon in 1969, and the NEPTUNE program (NorthEast Pacific Time-Integrated Undersea Networked Experiments) has that same kind of ambition and scope. By 2005, this broad coalition wants to wire the entire Juan de Fuca crustal plate with fiber-optic cable, connecting an array of seafloor observatories to the Internet. For some US$100 million, the project promises grand payoffs in many different ways: pure research, advances in equipment, public education, disaster preparedness, and even the space program. "The NEPTUNE approach also holds implications for the exploration of oceans elsewhere in our solar system," says a 2000 feasibility study, referring to Jupiter's icy moon Europa.
The plans call for more than 30 seafloor instrument stations and some 3200 kilometers of optical cable, connected to shore in Victoria, British Columbia, and Nedonna Beach, Oregon. Stations will have several kilowatts of power and bandwidth in the gigabits per second. "There will likely be future extensions further into the subarctic and subtropical gyresareas of the Pacific Ocean with important influences on global weather and ocean food chains," says another planning report. A public science center in tourist-friendly Victoria is an attractive option, and live video of the deep sea could be served to the Web along with torrents of other data.
The Juan de Fuca plate lies in U.S. and Canadian waters. The NEPTUNE coalition thus involves educational institutions, industry, and government agencies of at least two nations. The key partners that have fostered the program since 1998 are the University of Washington, Woods Hole Oceanographic Institution, the Jet Propulsion Laboratory, and the Pacific Marine Environmental Laboratory (run by the National Oceanic and Atmospheric Administration). But interest is widespread in high-tech industry and other nations with strong science programsafter all, the project will advance not just Earth science, but ecology, marine biology, fisheries, robotics, computer science, and electrical engineering as well.
The prime source of funding will be the American public, through the National Science Foundation's Ocean Observatories Initiative. A Canadian counterpart, NEPTUNE Canada, is working in parallel across the border. But if the undertaking succeeds, the whole world will benefit from the unprecedented knowledge to be gained.